rename package

src/llamafactory/train/ppo/utils.py

@@ -0,0 +1,59 @@
+import json
+from contextlib import nullcontext
+from typing import TYPE_CHECKING, Dict, List, Literal, Optional
+
+import torch
+from transformers.integrations import is_deepspeed_zero3_enabled
+
+from ...extras.packages import is_requests_available
+
+
+if TYPE_CHECKING:
+    from transformers import PreTrainedModel
+    from trl import AutoModelForCausalLMWithValueHead
+
+if is_requests_available():
+    import requests
+
+
+def get_rewards_from_server(server_url: str, messages: List[str]) -> List[torch.Tensor]:
+    headers = {"Content-Type": "application/json"}
+    payload = {"model": "model", "messages": messages}
+    response = requests.post(server_url, json=payload, headers=headers)
+    rewards = json.loads(response.text)["scores"]
+    return torch.Tensor(rewards)
+
+
+def replace_model(model: "AutoModelForCausalLMWithValueHead", target: Literal["default", "reward"]) -> None:
+    if is_deepspeed_zero3_enabled():
+        import deepspeed  # type: ignore
+
+        params = [model.v_head.summary.weight, model.v_head.summary.bias]
+        context_maybe_zero3 = deepspeed.zero.GatheredParameters(params, modifier_rank=0)
+    else:
+        context_maybe_zero3 = nullcontext()
+
+    with context_maybe_zero3:
+        if target == "reward":  # save default head temporarily
+            setattr(model, "default_head_weight", model.v_head.summary.weight.data.detach().clone())
+            setattr(model, "default_head_bias", model.v_head.summary.bias.data.detach().clone())
+
+        model.pretrained_model.set_adapter(target)  # set the LoRA adapter to be active
+        model.v_head.summary.weight.data = model.get_buffer("{}_head_weight".format(target)).detach().clone()
+        model.v_head.summary.bias.data = model.get_buffer("{}_head_bias".format(target)).detach().clone()
+
+
+def dump_layernorm(model: "PreTrainedModel") -> Dict[str, torch.Tensor]:
+    layer_norm_params = {}
+    for name, param in model.named_parameters():
+        if param.data.dtype == torch.float32:
+            layer_norm_params[name] = param.data.detach().clone()
+            param.data = param.data.to(model.config.torch_dtype)
+
+    return layer_norm_params
+
+
+def restore_layernorm(model: "PreTrainedModel", layernorm_params: Optional[Dict[str, torch.Tensor]] = None) -> None:
+    for name, param in model.named_parameters():
+        if name in layernorm_params:
+            param.data = layernorm_params[name]